That safety ground is ineffective - as explained previously.
You must confirm your earth ground is a single point earth ground. That is THE most critical component of a protection 'system'. Best protectors connect low impedance (ie less than 10 feet) to that ground. Wall receptacle safety ground clearly is not earth ground. ... Then no current is inside hunting for earth destructively via all appliances.
That APC must connect low impedance (ie hardwire has no sharp bends) to
earth ground. Otherwise joules in a potentially destructive surge simply use safety ground to find earth destructively via any nearby appliance.
A wall receptacle ground is not and cannot be an earth ground. Various grounds exist. Motherboard ground is different from chassis ground is different from floating ground in other appliances is different from wall receptacle ground is different from ground bus in a breaker box is different from a static electric ground is different from earth ground. Many are interconnected and still completely different.
One critical term is impedance. Surges must connect low impedance (ie less than 10 feet) to single point earth ground (all four words have electrical significance).
Protection means a surge current is not anywhere inside. Once inside, then nothing (as in nothing) can avert a hunt for earth destructively via appliances. Effective protectors always connect to earth BEFORE a surge can enter a building. True today as it was over 100 years ago.
BTW, best protection at each ethernet port is already inside that port. Your concern is a surge that can overwhelm that already existing, robust protection. That is always done at the service entrance - a low impedance connection to
earth.
No protector does protection - not one. Effective protectors are connecting devices to what does that protection - single point
earth ground.